EFRI 2-DARE: Few-layer and Thin-film Black Phosphorus for Photonic Applications

光子技术在现代社会中无处不在：红外探测器和调制器使光通信和互联网成为可能，移动设备中的小型相机使瞬间记录珍贵时刻成为可能，太阳能电池提供环保电力。传统的光子技术通常使用特定的材料来覆盖特定的波长范围，而集成多种类型的光子材料来覆盖更广泛的波长范围是非常具有挑战性的。该EFRI团队将研究基础光学科学，并探索一种新型二维（2D）材料黑磷（BP）的实际光子应用，该材料可以覆盖从可见光到中红外的宽波长范围，并且由于其分层结构，可以很容易地与其他光子平台集成。该团队将开发大规模黑磷合成、材料表征、BP器件实现和测试的方法，从而为基于黑磷的光子技术奠定基础。该项目将改变依赖于光学成像、传感和通信的许多技术领域，为国家光子学计划（NPI）做出贡献。该团队由来自四所大学（耶鲁大学、麻省理工学院、南加州大学和圣路易斯华盛顿大学）的五名研究人员组成，涵盖了包括材料科学、物理学和工程学在内的多个学科。该EFRI项目还将提供不同层次的学生，特别是那些来自代表性不足群体的学生，以及由EFRI团队培养的具有多学科研究经验的博士后，以及通过与工业和国际合作伙伴的互动。该项目将利用最近重新发现的二维层状黑磷来开发用于光通信和红外成像的新型光子器件，同时探索其与其他二维（如石墨烯）和块状（如硅）材料的集成。特别是，该团队将利用BP？具有层数的宽可调谐带隙及其鲁棒的各向异性激子，用于探索新的光学科学和改变现有的光子技术。建立少层和薄膜BP的理论、合成、封装和表征方法，以及BP光子器件性能的制造和基准测试，将为光子器件的这种范式转变奠定基础。在科学上，探索各向异性激子及其在少层BP中的电场可调性将促进我们对低晶体对称性材料中许多体物理的基本认识。在技术上，高载流子迁移率、直接带隙和强光-BP相互作用将使许多高性能BP光子学器件得以实现，特别是在战略关键的近红外和中红外波长范围内。

Photonic technologies have become ubiquitous in our modern society: infrared photodetectors and modulators enable optical communications and the internet, compact cameras in mobile devices make the instantaneous recording of precious moments possible, and solar cells provide environmentally-friendly electricity. Traditional photonics technologies often use a specific material to cover a particular wavelength range, with integration of multiple types 0f photonic materials to cover a broader range highly challenging. This EFRI team will investigate fundamental optical sciences and explore practical photonic applications of a novel two-dimensional (2D) material, black phosphorus (BP), which can cover a broad wavelength range from visible to mid-infrared and can be easily integrated with other photonic platforms due to its layered structure. The team will develop approaches for large-scale black phosphorus synthesis, material characterization, and BP device realization and testing, thus establishing the foundation for black phosphorus based photonic technologies. This project will transform many technological areas relying on optical imaging, sensing and communications, contributing to the National Photonics Initiative (NPI). The team consists of five investigators from four universities (Yale University, Massachusetts Institute of Technology, University of Southern California, and Washington University in St. Louis) and covers multiple disciplines including material sciences, physics, and engineering. This EFRI program will also provide students at different levels, especially those from underrepresented groups, and postdocs with multidisciplinary research experience fostered by the EFRI team, as well as through interactions with the industrial and international partners. This project will leverage recently rediscovered 2D layered black phosphorus to develop novel photonic devices for optical communications and infrared imaging, while exploring its integration with other 2D (e.g. graphene) and bulk (e.g. silicon) materials. In particular, the team will utilize BP?s widely tunable bandgap with layer number and its robust, anisotropic excitons to explore new optical sciences and to transform present photonic technologies. Establishing the theory, synthesis, encapsulation, and characterization approaches of few-layer and thin-film BP, as well as the fabrication and benchmarking of BP photonic device performance will build the foundation of this paradigm shift in photonic devices. Scientifically, exploration of anisotropic excitons and their tunability by electric field in few-layer BP will advance our basic understanding of many body physics in materials with low crystalline symmetry. Technologically, high carrier mobility, direct bandgap and strong light-BP interaction will enable the realization of a number of high performance BP photonics devices especially in strategically critical near- and mid-infrared wavelength range.